Measuring instrument.



W. H. BRISTOL.

MEASURING INSTRUMENT.

APPLIUATION FILED 00T. 2, 1913.

1,106,341. Patented Aug.4,1914.

v ments in Measuring Vil@ UNITED salaries eATENT onirica.

vWlIiIiIAlll. H; BRISTOL, OF WATERBURY, CONNECTICUT,` ASSIGNOR T0 THE BRISTOL COMPANY, lOIF WATIERBURY, CONNECTICUT, .A CORPORATION OF CONNECTICUT.

MEASURING INSTRUMENT.

y Specification of Letters Patent. Application tiled October 2, 1913.

therefrom, the move under Furthermore,

lPatented Aug. 4, 1914.

. serial No. 792,924.

inner end remaining free t variation of pressure thereon. the diaphragins with the exinnermost one are centrally perforated to provide a centrally disposed cylindrical opening l therethrough and registering with the opening ll aforesaid.

r o the free end of the series of diaphragms is xedly secured a strip or bar 1G, of sulciently rigid material, extending outwardly in the opening l5 for a portion of its length and then turned over at .right angles thereto. This strip 16 thus partakes of any motion of the diaphragm; and the turned over portion thereof is provided with a narrow slot 17 through which is adapted to pass a spiral member 18 preferably of a fiat strip of metal twisted to the desired pitch and having its ends pointed. The said is mounted to turn about the longitudinal axis of the diaphragms in suitable bearings 19 and `20 provided to receive the former To all w/Lom t may concern Be it known that I, WILLIAM H. BRISTOL, a Citizen of the United States, and a resident of Waterbury, .in the county of New Haven and State of Connecticut, have invented certain new and useful Improve- Instruments, of which the following is a specification.

The invention relates to measuring instruments in which a small motion of an actuated `member is to be .multiplied for indicating or recording purposes, for example, and as one embodiment of the invention, to apparatus for measuring variation of pres sure, more particularly through the effect of-a difference of pressure upon an expansible member or casing.

It has for its object to afford a simple, compact, dead-beat instrument, which, though extremely accurate and sensitive for ranges of low as well as high pressures, is so constructed as to be able to withstand severe treatment without loss of accuracy of indication.

It has for a further object to dispense with all complicated multiplying mechaciently below the turned over portion of strip 16 to insure the free action of the diaphragms. The other bearingI 20 is retained by an arm 22 extending from the outer face of the casing 10 over the opening l1.

suitable indicating arm or pointer 23 is attached to the. spiral member 18 near its parts which may be bled.

To this end, the invention consists in certain fea-tures of construction more particularly described hereinafter, and shown in h dial 24 upon the outer A the accompanying drawing, in whichsuitably graduated Figure l is a plan view of an indicating face of the casing l0. It 1s to be. understood, pressure gage embodying the invention. of course, that although the invention 1s herein shown as applied specifically to an thereof taken on indicating pressure gage, that 1t 1s equally Fig. 2 is a vertical sectio the line 2-2, Fig. 1.

Similar characters of reference designate applicable to a recording gage. It will be corresponding parts throughout the several .readily understood, moreover, that as the views. diaphragms move inwardly and outwardly Referring to the drawings, l0 designates under the influence of the difference of presa suitable casing .for the instrument, and is provided with a central circular opening l1 and an inlet l2 through which latter the fluid whose pressure it is desired to measure may be f introduced. Centrally disposed expansible member one or more fiexi shown, a'plurality and which may be applied within the diaphragms, if desired, instead of outside as herein shown, that the strip 16 will acquire a similar motion. Theslot 17 thereof, in engaging the spiral member 18, will therefore effect aA rotary movement of the latter which is` communicated to its attached pointer 23. This in turn will serve as a measure of the applied pressure, by which term is also to be understood pressures below atmospheric pressure. In case of a Huid eX- within this Casing- 1s an preferably consisting of ble diaphragms 13. As

sure exerted thereon by the introduced fluid,

i a spiral member of varying pitch, the indipansible under variation of temperature and retained in the casing l0, inlet 12 is of course unnecessary, andthe variation of the volume of the fluid will serve as a measure of the temperature due to the pressure effect there'- o upon the diaphragme.

The instrument thus constructed is compdsed of but few, simple and accessible parts which may be readily and economically produced, will be dead-beat in its indication and su'iciently rigid to withstand amount of rough treatment. by reducing the number of diaphragms, an apparatus may be obtained which is unusually thin, a feature extremely desirable in many instances. Moreover, by providing cations need not be uniform for equal increments of pressure.

l claim:- l. A pressuregage, comprising: a suitably diaphragme forming an expansible member adapted to vary in length under pressure variations, the perfo-rations of said diaphragms registering with that of said casing and one end of said expansible member being free to move; a member secured to the said free end of the expansible member` and eX- tending into the perforations of the diaphragme; a spiral member within the perforations of said diaphragme and engaged by said member extending from the free end of the diaphragme to be oscillated thereby;

a reasonable Furthermore,`

perforated suitable bearing members for the spiral member and secured to said casing; and a measuring arm attached to vsaid spiral member to move over the said casing as the expansible member varies in length.

2. A pressure gage, comprising: a suit- 40 able casing centrally perforated; a plurality oit perforated eXpansible diaphragms, the perforations thereof registering with that of said casing and one end of said diaphragms being ixedly attached to said casing forming therewith a sealed chamber; a suitable inlet thereto for fluid underV pressure; ay slotted member secured to thevfree end of said diaphragme and extending into the perforations thereof; a spiral mem-ber engaged by the slot of said slotted member; a bracket extending inwardly from said casing into the perforations of said diaphragme and providing a bearing for the spiral member; an arm extending over said casing and providing a second bearing for said spiral member; and an indicating ar'm attached to -saidspiral member adapted to move over the said casing ars/the length of said expansible chamber is varied.

Signed at New York, in the county of New York, and State of New York, this 30th day of Sept., A. D. 1913.

vwiLLmM H. Bmsron o Witnesses:

FBEDK l?. SGHNETZ, HELEN 'nn MOYA. 

